Disable charge pump on Knight of tone
Hello Pedal Builders,
I have build a Knight of Tone from PCB Guitar Mania which plays very well. Now the building docs https://pcbguitarmania.com/wp-content/u ... g-Docs.pdf recommend to try it without the Charge Pump if using it with a lot of overdrive.
The doc says there is a graphic which shows howto bypass the charge pump.
Unfortunately I‘m not able to find the required information or graphic.
Looking at the schematic, I’m wondering if I simply need to remove IC3 and that‘s it. Can somebody confirm that?
If I want to have it switchable how can I do this?
Thanks for your help and feedback.
I have build a Knight of Tone from PCB Guitar Mania which plays very well. Now the building docs https://pcbguitarmania.com/wp-content/u ... g-Docs.pdf recommend to try it without the Charge Pump if using it with a lot of overdrive.
The doc says there is a graphic which shows howto bypass the charge pump.
Unfortunately I‘m not able to find the required information or graphic.
Looking at the schematic, I’m wondering if I simply need to remove IC3 and that‘s it. Can somebody confirm that?
If I want to have it switchable how can I do this?
Thanks for your help and feedback.
Last edited by falcon75 on 17 Oct 2022, 18:26, edited 1 time in total.
- mauman
- Resistor Ronker
Remove IC3 (charge pump). Remove D14 and D15 and replace them with straps, or leave them in and strap around them. The 9V input will then become your V+. You won't need C11, C12 or C13 but it won't hurt to leave them in if they're already installed.
The best way to make it switchable is to move the DC protection and charge pump circuit to a separate vero board, then run the 18V vero output and 9V to lugs 1 and 3 of a SPDT, with lug 2 of the SPDT to the +9V input of the PCB. If you're interested let me know and I can post a diagram.
The best way to make it switchable is to move the DC protection and charge pump circuit to a separate vero board, then run the 18V vero output and 9V to lugs 1 and 3 of a SPDT, with lug 2 of the SPDT to the +9V input of the PCB. If you're interested let me know and I can post a diagram.
- Manfred
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If you disconnect pin 4 of the LT1044 from ground it should no longer be activated, so switching would be possible, try it.
A simple possibility would be to use a 5V power supply.
A simple possibility would be to use a 5V power supply.
Hello
I have bought a knight of tone replica but i have an issue with it.
When i put the drive on 75/100 on one side, there is a rather loud hum coming out of the pedal. It does the thing on both sides and on the 3 modes (od, disto, boost). It becomes very disturbing when the both sides are switched on.
Is it normal or do you think there is an issue that i could fix easily?
I dont think it s due to my power supply because i have 0 problem on other pedals.
I have bought a knight of tone replica but i have an issue with it.
When i put the drive on 75/100 on one side, there is a rather loud hum coming out of the pedal. It does the thing on both sides and on the 3 modes (od, disto, boost). It becomes very disturbing when the both sides are switched on.
Is it normal or do you think there is an issue that i could fix easily?
I dont think it s due to my power supply because i have 0 problem on other pedals.
I have a power supply that can adapt the voltage. So if i run the pedal on 5v or 6v with no modification inside, it should fix the hum?
- Manfred
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Does the hum occur with or without input signal ?When i put the drive on 75/100 on one side, there is a rather loud hum coming out of the pedal. It does the thing on both sides and on the 3 modes (od, disto, boost). It becomes very disturbing when the both sides are switched on.
Is the noise humming with the line frequency or does it sound like a different frequency ?
No hum when pedal is not switched on
Hum happens when pedal is switched on and no guitar is plugged and same when plugged (maybe different sound but not very different)
Hum is not linked to other pedal cause it happens even when alone in the pedalboard
I tried with 6v power and it doesnt change anything
The hum is in the background so not linked to the line frequency i think. The hum gets louder with the drive or volume of pedal and more trebly with the tone.
Hum happens when pedal is switched on and no guitar is plugged and same when plugged (maybe different sound but not very different)
Hum is not linked to other pedal cause it happens even when alone in the pedalboard
I tried with 6v power and it doesnt change anything
The hum is in the background so not linked to the line frequency i think. The hum gets louder with the drive or volume of pedal and more trebly with the tone.
- Manfred
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This could be oscillation in the circuit.BILBO15 wrote: ↑07 Sep 2023, 08:59 No hum when pedal is not switched on
Hum happens when pedal is switched on and no guitar is plugged and same when plugged (maybe different sound but not very different)
Hum is not linked to other pedal cause it happens even when alone in the pedalboard
I tried with 6v power and it doesnt change anything
The hum is in the background so not linked to the line frequency i think. The hum gets louder with the drive or volume of pedal and more trebly with the tone.
Short-circuit the input to ground and see what happens.
You mean moving the link going out of the jack to the ground?Manfred wrote: ↑07 Sep 2023, 18:55This could be oscillation in the circuit.BILBO15 wrote: ↑07 Sep 2023, 08:59 No hum when pedal is not switched on
Hum happens when pedal is switched on and no guitar is plugged and same when plugged (maybe different sound but not very different)
Hum is not linked to other pedal cause it happens even when alone in the pedalboard
I tried with 6v power and it doesnt change anything
The hum is in the background so not linked to the line frequency i think. The hum gets louder with the drive or volume of pedal and more trebly with the tone.
Short-circuit the input to ground and see what happens.
- Manfred
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https://streamable.com/886ggh?src=player-page-share
Video of the sound.
It is not nvery noticeable but the sound happens too when only one side of the pedal is engaged, just louder with both sides
Video of the sound.
It is not nvery noticeable but the sound happens too when only one side of the pedal is engaged, just louder with both sides
- Manfred
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This sounds like noise.
The cause could be bad noise OP-amps , where did you buy them?
I see they are mounted the OP-amps sockets, so you can replace them with low noise types like NE5532 to see if the noise intensity goes down.
Do you have an oscilloscope?
The cause could be bad noise OP-amps , where did you buy them?
I see they are mounted the OP-amps sockets, so you can replace them with low noise types like NE5532 to see if the noise intensity goes down.
Do you have an oscilloscope?
- Manfred
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This is just a test to see if the noise is gone or becomes less intesive using the NE5532s
If it would be better, it is then the question whether the sound changes depending on the type of OP amp.
- Manfred
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Solder a 22pF capacitor in parallel to R1 and RB1 and see if the radio reception is gone.
Otherwise it could also be a wiring problem.
Please give us detailed shots.
- Manfred
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Did you make any progress in troubleshooting?